Online research in philosophy

In this new volume in the Oxford Psychology Series, the author presents a highly readable account of the cognitive unconscious, focusing in particular on the problem of implicit learning. Implicit learning is defined as the acquisition of knowledge that takes place independently of the conscious attempts to learn and largely in the absence of explicit knowledge about what was acquired. One of the core assumptions of this argument is that implicit learning is a fundamental, "root" (...) process, one that lies at the very heart of the adaptive behavioral repertoire of every complex organism. The author's goals are to outline the essential features of implicit learning that have emerged from the many studies that have been carried out in a variety of experimental laboratories over the past several decades; to present the various alternative perspectives on this issue that have been proposed by other researchers and to try to accommodate these views with his own; to structure the literature so that it can be seen in the context of standard heuristics of evolutionary biology; to present the material within a functionalist approach and to try to show why the experimental data should be seen as entailing particular epistemological perspectives; and to present implicit processing as encompassing a general and ubiquitous set of operations that have wide currency and several possible applications. Chapter 1 begins with the core problem under consideration in this book, a characterization of "implicit learning" as it has come to be used in the literature. Reber puts this seemingly specialized topic into a general framework and suggests a theoretical model based on standard heuristics of evolutionary biology. In his account, Reber weaves a capsule history of interest in and work on the cognitive unconscious. Chapter 2 turns to a detailed overview of the experimental work on the acquisition of implicit knowledge, which currently is of great interest. Chapter 3 develops the evolutionary model within which one can see learning and cognition as richly intertwining issues and not as two distinct fields with one dominating the other. Finally, Chapter 4 explores a variety of entailments and speculations concerning implicit cognitive processes and their general role in the larger scope of human performance. (shrink)

In this paper I evaluate Michael Dummett’s notion of implicit knowledge by examining his answers to these two questions: (1) Why should we ascribe knowledge of a meaning-theory of a language to a language-user, and why the mode of this knowledge is implicit, but not pure theoretical, pure practical, or unconscious in a Chomskian sense? (2) How could a meaning-theory, which is known implicitly, function as a rule to be followed by the language-user? To answer (...) (1) I shall construct Dummett’s argument for implicit knowledge, which includes three sub-arguments: the argument from rationality, the argument from dilemma, and the argument from communicability. As to (2), I argue that Dummett’s answer confuses knowledge of a meaning-theory with knowledge of a set of grammars. (shrink)

In this response, we start from first principles, building up our theory to show more precisely what assumptions we do and do not make about the representational nature of implicit and explicit knowledge (in contrast to the target article, where we started our exposition with a description of a fully fledged representational theory of knowledge (RTK). Along the way, we indicate how our analysis does not rely on linguistic representations but it implies that implicit knowledge (...) is causally efficacious; we discuss the relationship between property structure implicitness and conceptual and nonconceptual content; then we consider the factual, fictional, and functional uses of representations and how we go from there to consciousness. Having shown how the basic theory deals with foundational criticisms, we indicate how the theory can elucidate issues that commentators raised in the particular application areas of explicitation, voluntary control, visual perception, memory, development (with discussion on infancy, theory of mind [TOM] and executive control, gestures), and finally models of learning. (shrink)

Implicit knowledge is perhaps better understood as latent knowledge so that it is readily apparent that it contrasts with explicit knowledge in terms of the form of the knowledge representation, rather than by definition in terms of consciousness or awareness. We argue that as a practical matter any definition of the distinction between implicit and explicit knowledge further involves the notion of control.

Gesture does not have a fixed position in the Dienes & Perner framework. Its status depends on the way knowledge is expressed. Knowledge reflected in gesture can be fully implicit (neither factuality nor predication is explicit) if the goal is simply to move a pointing hand to a target. Knowledge reflected in gesture can be explicit (both factuality and predication are explicit) if the goal is to indicate an object. However, gesture is not restricted to these (...) two extreme positions. When gestures are unconscious accompaniments to speech and represent information that is distinct from speech, the knowledge they convey is factuality-implicit but predication-explicit. (shrink)

The article deals with historical dynamics of implicit and intuitive elements of mathematical knowledge. The author describes historical dynamics of implicit and intuitive elements and discloses a historical and evolutionary mechanism of building up mathematical knowledge. Each requirement to increase the level of theoretical rigor in mathematics is historically realized as a three-stage process. The first stage considers some general conditions of valid mathematical knowledge recognized by the mathematical community. The second one reveals the level (...) of theoretical rigor increasing, while the third one is characterized by explication of the hidden lemmas. A detailed discussion of historical substantiation of the basic algebra theorem is conducted according to the proposed technique. (shrink)

In the scientific study of mind a distinction is drawn between explicit knowledge–knowledge that can be elicited from a subject by suitable inquiry or prompting, can be brought to consciousness, and externally expressed in words–and implicit knowledge–knowledge that cannot be elicited, cannot be made directly conscious, and cannot be articulated. Michael Polanyi (1967) argued that we usually ‘know more than we can say’. The part we can articulate is explicitly known; the part we cannot is (...) implicit. (shrink)

By introducing a name 'one meter' and stipulating that it refers to the length of stick S, the stipulator appears to be in a position to gain immediate (and arguably a priori) knowledge of a mind- and language-independent fact-the fact that the length of stick S is one meter. It appears that other users of the name can gain this knowledge only through empirical enquiry. I argue that this presents a paradox. After clarifying the nature of the paradox, (...) I offer a solution by arguing that, contrary to appearances, other users of 'one meter' implicitly knew that the length of stick S is one meter before learning the name, as did the stipulator prior to introducing the name. There is some distinct knowledge that other users of the name can only gain empirically, but the stipulator cannot gain this knowledge without empirical enquiry either. (shrink)

In the scientific study of mind a distinction is drawn between explicit knowledge— knowledge that can be elicited from a subject by suitable inquiry or prompting, can be brought to consciousness, and externally expressed in words—and implicit knowledge—knowledge that cannot be elicited, cannot be made directly conscious, and can- not be articulated. Michael Polanyi (1967) argued that we usually ‘know more than we can say’. The part we can articulate is explicitly known; the part we (...) cannot is implicit. (shrink)

In Dienes & Perner's analysis, implicitly represented knowledge differs from explicitly represented knowledge only in the attribution of properties to specific events and to self-awareness of the knower. This commentary questions whether implicit knowledge should be thought of as being represented in the same conceptual vocabulary; rather, it may involve a quite different form of representation.

"Draws on philosophers, political theorists, activists, and poets to explain how unspoken and unspeakable knowledge is important to racial and gender formation; offers a usable conception of implicit understanding"--Provided by publishers.

The concept of tacit knowledge is widely used in social sciences to refer to all those knowledge that cannot be codified and have to be transferred by personal contacts. All this literature has been affected by two kind of biases : (1) the interest has been focused more on the result (tacit knowledge) than on the process (implicit learning); (2) tacit knowledge has been somehow reduced to physical skills or know-how; other possible forms of tacit (...) knowledge have been neglected. These two biases seem interconnected one with each other. A greater consideration of the role and relevance of implicit learning allows us to consider tacit knowledge as something more than pure physical skills or know how. This is the first step in order to develop more detailed categorisation of the different forms that tacit knowledge can assume. (shrink)

The notion of nonconceptual content in Dienes & Perner's theory is examined. A subject may be in a state with nonconceptual content without having the concepts that would be used to describe the state. Nonconceptual content does not seem to be a clear-cut case of either implicit or explicit knowledge. It underlies a kind of practical knowledge, which is not reducible to procedural knowledge, but is accessible to the subject and under voluntary control.

A comprehensive theory of implicit and explicit knowledge must explain phenomenal knowledge (e.g., knowledge regarding one's affective and motivational states), as well as propositional (i.e., “fact”-based) knowledge. Findings from several research areas (i.e., the subliminal mere exposure effect, artificial grammar learning, implicit and self-attributed dependency needs) are used to illustrate the importance of both phenomenal and propositional knowledge for a unified theory of implicit and explicit mental states.

Dienes & Perner's (D&P's) target articles proposes an analysis of explicit knowledge based on a progressive transformation of implicit into explicit products, applying this gradient to different aspects of knowledge that can be represented. The goal is to integrate a philosophical concept of knowledge with relevant psychophysical and neuropsychological data. D&P seem to fill an impressive portion of the gap between these two areas. We focus on two examples where a full synthesis of theoretical and empirical (...) data seems difficult to establish and would require further refinement of the model: action representation and the closely related consciousness of action, which is in turn related to self-consciousness. (shrink)

This commentary discusses how Dienes & Perner's theory of implicit and explicit knowledge applies to memory research. As currently formulated, their theory does seem to account simultaneously for population dissociations and dissociations between conceptual and perceptual priming tasks. In addition, the specification of four distinct memorial states (correlated with different recognition test responses) faces important methodological challenges.

Dienes & Perner (D&P) argue that nondeclarative knowledge can take multiple forms. We provide empirical support for this from two related lines of research about the development of mathematical reasoning. We then describe how different forms of procedural and declarative knowledge can be effectively modeled in Anderson's ACT-R theory, contrasting this computational approach with D&P's logical approach. The computational approach suggests that the commonly observed developmental progression from more implicit to more explicit knowledge can be viewed (...) as a consequence of accumulating and strengthening mental representations. (shrink)

Holding content explicitly requires a form of self knowledge. But what does the relevant self knowledge look like? Using theory of mind as an example, this paper argues that the correct answer to this question will have to take into account the crucial role of language based deliberation, but warns against the standard assumption that explicitness is necessary for ascribing awareness. It argues in line with Bayne that intentional action is at least an equally valid criterion for awareness. (...) This leads to a distinction between different levels of implicitness. Postulating these different levels, it is argued, allows us to make better sense of the empirical literature on early false belief task abilities. (shrink)

Analogical cognition refers to the ability to detect, process, and learn from relational similarities. The study of analogical and similarity cognition is widely considered one of the ‘success stories’ of cognitive science, exhibiting convergence across many disciplines on foundational questions. Given the centrality of analogy to mind and knowledge, it would benefit philosophers investigating topics in epistemology and the philosophies of mind and language to become familiar with empirical models of analogical cognition. The goal of this essay is to (...) describe recent empirical work on analogical cognition as well as model applications to philosophical topics. Topics to be discussed include the epistemological distinction between implicit knowledge and explicit knowledge, the debate between empiricists and nativists, the frame problem, expertise, creativity and autism, cognitive architecture, and relational knowledge. Particular attention is given to Dedre Gentner and colleague’s structure-mapping theory – the most developed and widely accepted model of analogical cognition. (shrink)

In Boghossian's 1997 paper, 'Analyticity' he presented an account of a prioriknowledge of basic logical principles as available by inference from knowledge of their role in determining the meaning of the logical constants by implicit definitiontogether with knowledge of the meanings so-determined that we possess through ourprivileged access to meaning. Some commentators (e.g. BonJour (1998), Glüer (2003),Jenkins (2008)) have objected that if the thesis of implicit definition on which he relieswere true, knowledge of the meaning (...) of the constants would presuppose knowledge of the very logical principles knowledge of which the account purports to explain. Aconsequence would seem to be that implicit definition is incompatible with privilegedaccess. I argue that whilst it is possible for Boghossian to defend against theseobjections the form of argument he proposes does exhibit a subtle form of questionbegging such that it exhibits a transmission of warrant-failure. (shrink)

from the fact that the subject reacts faster to those words than to words that were not on the list. The subject.

The communication of emotion in music has with few exceptions, as L. B. Meyer´s Emotion and Meaning in Music (1956) and the contour theory (Kivy 1989, 2002), focused on music structure as representations of emotions. This implies a semiotic approach - the assumption that music is a kind of language that could be read and decoded. Such an approach is largely restricted to the conscious level of knowing, understanding and communication. We suggest an understanding of music and emotion based on (...) action-perception theory - present moment perception, implicit knowledge and imitation. This theory does not demand consciousness or the use of signs. Neuroscientific findings (adaptive oscillators, mirror neurons) are in concordance with our suggestion. Recently these findings have generated articles on empathy – relevant to the understanding of music and emotion. (shrink)

Dienes & Perner's theoretical framework should be applicable to two related areas: technological innovation and the psychology of scientific reasoning. For the former, this commentary focuses on the example of nuclear weapon design, and on the decision to launch the space shuttle Challenger. For the latter, this commentary focuses on Klayman and Ha's positive test heuristic and the invention of the telephone.

The concept of unconscious knowledge is fundamental for an understanding of human thought processes and mentation in general; however, the psychological community at large is not familiar with it. This paper offers a survey of the main psychological research currently being carried out into cognitive processes, and examines pathways that can be integrated into a discipline of unconscious knowledge. It shows that the field has already a defined history and discusses some of the features that all kinds of (...) unconscious knowledge seem to share at a deeper level. With the aim of promoting further research, we discuss the main challenges which the postulation of unconscious cognition faces within the psychological community. (shrink)

This paper presents a skill learning model CLARION. Different from existing models of mostly high-level skill learning that use a top-down approach (that is, turning declarative knowledge into procedural knowledge through practice), we adopt a bottom-up approach toward low-level skill learning, where procedural knowledge develops first and declarative knowledge develops later. Our model is formed by integrating connectionist, reinforcement, and symbolic learning methods to perform on-line reactive learning. It adopts a two-level dual-representation framework (Sun, 1995), with (...) a combination of localist and distributed representation. We compare the model with human data in a minefield navigation task, demonstrating some match between the model and human data in several respects. © 2001 Cognitive Science Society, Inc. All rights reserved. (shrink)

Early childhood is characterized by many cognitive developmentalists as a period of considerable change with respect to representational format. Dienes & Perner present a potentially viable theory for the stages involved in the increasingly explicit representation of knowledge. However, in our view they fail to map their multi-level system of explicitness onto cognitive developmental changes that occur in the first years of life. Specifically, we question the theory's heuristic value when applied to the development of early mind reading and (...) categorization. We conclude that the authors fail to present evidence that dispels the view that knowledge change in these areas is dichotomous. (shrink)

For further development of organic agriculture, it will become increasingly essential to integrate experienced innovative practitioners in research projects. The characteristics of this process of co-learning have been transformed into a research approach, theoretically conceptualized as “experiential science” (Baars 2007 , Baars and Baars 2007 ). The approach integrates social sciences, natural sciences, and human sciences. It is derived from action research and belongs to the wider field of transdiscliplinary research. In a dialogue-based culture of equality and mutual exchange the (...) principal of a “bottom-up” experiential learning process can be stimulated and fully reflective. It provides an opportunity to develop organic agriculture as multiple best-practices based on transdisciplinary projects, cases studies, and case series. The aim of the article is to describe the methodological characteristics and the theoretical and practical potential of experiential science for research in and development of organic farming. Three characteristic projects are outlined to illustrate the main elements of the methodology: the retrospective reflection on intuitive and experiential knowledge held by farmers; the knowledge derived from on-farm experimentation; the exchange of knowledge and experiences between farming pioneers within a “masterclass” setting. The study concludes that experiential science offers an important philosophical reconciliation process whereby a synthesis of different approaches to research becomes possible in solving real-life problems: quantitative and qualitative, subjective and objective, reductionistic and holistic, practice and science. Recognizing that there are multiple elements contributing to the process of acquiring knowledge, experiential science draws on a broad field of scientific methods thereby integrating the hermeneutic approach of social sciences and the Humanities with the established methods of contemporary natural science. (shrink)

Let R be an epistemic rule of the simplest type: "Accept sentence s!" Assume that R is a basic rule we actually follow: Our accepting the sentence cannot be explained by our following more fundamental rules of sentence-acceptance. Assume furthermore that we feel rationally obliged to follow R; that is, we all agree on the correctness of the epistemic norm N which says: We ought to accept s.

Dienes & Perner argue that the explicit representation of an individual to which a property is attributed requires explicit representation of the attributed property. The reasons for this conclusion are similar to the reasons why another of their conclusions may be considered suspect: A property may be explicit without an explicit representation of an individual or the predication of the property to an individual. We question the latter conclusion and draw connections to neurophysiological and cognitive evidence.

First published in 1984 as part of The Collected Papers of Bertrand Russell , Theory of Knowledge represents an important addition to our knowledge of Russell's thought. In this work Russell attempts to flesh out the sketch implicit in The Problems of Philosophy . It was conceived by Russell as his next major project after Principia Mathematica and was intended to provide the epistemological foundations for his work. Russell's subsequent difficulties in presenting his theory of knowledge, (...) brought on by what he considered to be devastating criticisms of Wittgenstein, led to both his abandonment of this work and to a major transformation in his thought. Theory of Knowledge , now available for the first time in paperback, gives us a picture of one of the great minds of the twentieth century at work. It is possible to see the unsolved problems left without disguise or evasion. This second edition has retained the full scholarly introduction. The photographs of the manuscript, appendices, and notes on textual matters have been eliminated to provide a concise and accessible guide to understanding both Russell's own thought and his relationship with Wittgenstein. (shrink)

We develop a logical system that captures two different interpretations of what extensive games model, and we apply this to a long-standing debate in game theory between those who defend the claim that common knowledge of rationality leads to backward induction or subgame perfect (Nash) equilibria and those who reject this claim. We show that a defense of the claim à la Aumann (1995) rests on a conception of extensive game playing as a one-shot event in combination with a (...) principle of rationality that is incompatible with it, while a rejection of the claim à la Reny (1988) assumes a temporally extended, many-moment interpretation of extensive games in combination with implausible belief revision policies. In addition, the logical system provides an original inductive and implicit axiomatization of rationality in extensive games based on relations of dominance rather than the usual direct axiomatization of rationality as maximization of expected utility. (shrink)

Martin Davies' criterion for the knowledge of implicit rules, viz. the causal systematicity of cognitive processes, is first exposed. Then the inference from causal systematicity of a process to syntactic properties of the input states is examined. It is argued that Davies' notion of a syntactic property is too weak to bear the conclusion that causal systematicity implies a language of thought as far as the input states are concerned. Next, it is shown that Davies' criterion leads to (...) a counterintuitive consequence: it groups together distributed connectionist systems with look-up tables. To avoid this consequence, a modified construal of causal systematicity is proposed and Davies' argument for the causal systematicity of thought is shown to be question-begging. It is briefly sketched how the modified construal links up with multiple dispositions of the same categorical base. Finally, the question of the causal efficacy of single rules is distinguished from the question of their psychological reality: implicit rules might be psychologically real without being causally efficacious. (shrink)

A brief historical comment on scientific knowledge as Socratic ignorance -- Some critical comments on the text of this book, particularly on the theory of truth Exposition [1933] -- Problem of Induction (Experience and Hypothesis) -- Two Fundamental Problems of the Theory of Knowledge -- Formulation of the Problem -- The problem of induction and the problem of demarcation -- Deductivtsm and Inductivism -- Comments on how the solutions are reached and preliminary presentation of the solutions -- Rationalism (...) and empiricism-deductivism and inductivism -- The possibility of a deductivist psychology of knowledge -- The Problem of Induction -- The infinite regression (Hume's argument) --The inductivist positions -- The Normal-Statement Positions -- The normal-statement positions: naive inductivism, strict positivism and apriorism -- Critique of strict positivism - twofold transcendence of natural laws -- The transcendental method - presentation of apriorism -- Critique of apriorism -- Kant and Fries -- Supplement to the critique of apriorism. (Psychologism and transcendentalism in Kant and Fries.-On the question of the empirical basis.) -- Probability Positions -- The probability positions - subjective belief in probability -- Statements about the objective probability of events -- Probability as an objective degree of validity of universal empirical statements -- One way of more closely defining the concept of the probability of a hypothesis (primary and secondary probability of hypotheses). The concept of simplicity -- The concept of the corroboration of a hypothesis - positivist, pragmatist and probabilistic interpretations of the concept of corroboration -- The infinite regression of probability statements -- Pseudo-Statement Positions -- The pseudo-statement positions: new formulation of the problem -- Natural laws as "instructions for the formation of statements" -- "True - false" or "useful - useless"? Consistent pragmatism --Difficulties of consistent pragmatism -- Tool and schema as purely pragmatic constructs -- Natural laws as propositional functions -- Conventionalism -- The pseudo-statement positions will temporarily be put away: conventionalism -- The three interpretations of axiomatic systems. (The circle of problems surrounding conventionalism) -- Conventionalist implicit and explicit definitions Propositional function and propositional equation -- Conventionalist propositional equations as tautological general implications -- Can axiomatic-deductive systems also be understood as consequence classes of pure propositional functions (of pseudo-statements)? -- The coordinative definitions of empiricism: synthetic general implications -- Conventionalist and empiricist interpretations, illustrated by the example of applied geometry -- Strictly Universal Statements and Singular Statements -- Implication and general implication -- General implication and the distinction between strictly universal and singular statements -- Universal concept and individual concept-class and element -- Strictly universal statements-the problem of induction and the problem of universals -- Comments on the problem of universals -- Back to the Pseudo-Statement Positions -- Return to the discussion of the pseudo-statement positions -- Symmetry or asymmetry in the evaluation of natural laws? -- The negative evaluation of universal statements. Critique of the strictly symmetrical interpretation of pseudo-statements -- An infinite regression of pseudo-statements -- An apriorist pseudo-statement position -- Interpretation of the critique up to this point; comments on the unity of theory and practice -- A last chance for the pseudo-statement positions -- Pseudo-Statement Positions and the Concept of Meaning -- The concept of meaning and logical positivism -- The concept of meaning and the demarcation problem-the fundamental thesis of inductivism -- Critique of the inductivist dogma of meaning -- Fully decidable and partially decidable empirical statements-the antinomy of the knowability of the world. (Conclusion of the critique of the pseudo-statement positions.) -- The dialectical and the transcendental corroboration of the solution -- Is the problem of induction solved? (shrink)

One of the main challenges in the philosophy of language is determining the form of knowledge of the rules of language. Michael Dummett has put forth the view that knowledge of the rules of language is a kind of implicit knowledge; some philosophers have mistakenly conceived of this type of knowledge as a kind of knowledge-that . In a recent paper in this journal, Patricia Hanna argues against Dummett’s knowledge-that view and proposes instead (...) a knowledge-how view in which knowledge of the rules of language is a kind of practical knowledge, like an agent’s non-propositional knowledge of counting. In this paper I argue, first, that Hanna misunderstands Dummett’s conception of knowledge of linguistic rules, and, second, that Dummett’s considerations of practical knowledge of language pose a problem for Hanna’s knowledge-how view. At the end of the paper, I briefly sketch an account of practical knowledge of language that meets the requirements set by Dummett. (shrink)

The degree to which information is encoded explicitly in a representation is related to the computational cost of recovering or using the information. Knowledge that is implicit in a system need not be represented at all, even implicitly, if the cost of recovering it is prohibitive.

This paper explicates the interaction between the implicit and explicit learning processes in skill acquisition, contrary to the common tendency in the literature of studying each type of learning in isolation. It highlights the interaction between the two types of processes and its various effects on learning, including the synergy effect. This work advocates an integrated model of skill learning that takes into account both implicit and explicit processes; moreover, it embodies a bottom-up approach (first learning implicit (...) knowledge and then explicit knowledge on its basis) towards skill learning. The paper shows that this approach accounts for various effects in the process control task data, in addition to accounting for other data reported elsewhere. (shrink)

The paper is sympathetic to the idea that speakers have implicit knowledge of the semantics of sub-sentential elements of language, loosely, of words. Implicit knowledge is knowledge which the subject need not be capable of articulating yet which is a genuine propositional attitude and it is to be contrasted with tacit knowledge which refers to an information-bearing state which, however, is not a genuine propositional attitude. I begin by defending the implicit knowledge (...) conception of speakers' knowledge of the meanings of words from a challenge articulated by Evans and then go on the offensive against positions which attempt to replace the notion of implicit knowledge in semantic theory by that of tacit knowledge. (shrink)

This article explicates the interaction between implicit and explicit processes in skill learning, in contrast to the tendency of researchers to study each type in isolation. It highlights various effects of the interaction on learning (including synergy effects). The authors argue for an integrated model of skill learning that takes into account both implicit and explicit processes. Moreover, they argue for a bottom-up approach (first learning implicit knowledge and then explicit knowledge) in the integrated model. (...) A variety of qualitative data can be accounted for by the approach. A computational model, CLARION, is then used to simulate a range of quantitative data. The results demonstrate the plausibility of the model, which provides a new perspective on skill learning. (shrink)

The paper is sympathetic to the idea that speakers have implicit knowledge of the semantics of sub-sentential elements of language, loosely, of words. Implicit knowledge is knowledge which the subject need not be capable of articulating yet which is a genuine propositional attitude and it is to be contrasted with tacit knowledge which refers to an information-bearing state which, however, is not a genuine propositional attitude. I begin by defending the implicit knowledge (...) conception of speakers' knowledge of the meanings of words from a challenge articulated by Evans and then go on the offensive against positions which attempt to replace the notion of implicit knowledge in semantic theory by that of tacit knowledge. (shrink)

Dienes and Perner’s theory is not a satisfactory theory of implicit knowledge because by endorsing the representational theory of knowledge, the authors also inadvertently accept that only explicit knowledge can be causally efficacious, and hence that implicit knowledge is an inert category. This conflation between causal efficacy, knowledge, and explicitness is made clear through the authors' strategy, which consists of attributing any observable effect to the existence of representations that are as minimally explicit (...) as needed to account for behavior. In contrast, we believe that causally efficacious and fully implicit knowledge exists, and is best embodied in frameworks that depart radically from classical assumptions. (shrink)

Some cases of implicit knowledge involve representations of (implicitly) known propositions, but this is not the only important type of implicit knowledge. Chomskian linguistics suggests another model of how humans can know more than is accessible to consciousness. Innate capacities to focus on a small range of possibilities, thereby ignoring many others, need not be grounded by inner representations of any possibilities ignored. This model may apply to many domains where human cognition “fills a gap” between (...) stimuli and judgment. (shrink)

A philosopher once asked me: “Paul, how do you collaborate?” He was puzzled about how I came to have more than two dozen co-authors over the past 20 years. His puzzlement was natural for a philosopher, because co-authored articles and books are still rare in philosophy and the humanities, in contrast to science where most current research is collaborative. Unlike most philosophers, scientists know how to collaborate; this paper is about the nature of such procedural knowledge. I begin by (...) discussing three related distinctions found in philosophy and cognitive science: knowledge how vs. knowledge that, procedural vs. declarative knowledge, and explicit vs. implicit knowledge. I then document the prevalence of collaboration in the sciences and its scarcity in philosophy. In order to characterize the sorts of procedural knowledge that make collaborative research possible and fruitful, I discuss how scientists collaborate, how they learn to collaborate, and why they collaborate. Contrary to some recent suggestions by philosophers, I will argue that knowledge how often does not always reduce to knowledge that, and that collaboration has many purposes besides the pursuit of power and resources. The relative scarcity of philosophical collaborations might be explained by the nature of philosophy, if the field is viewed as inherently personal or a priori. But I argue against this view in favor of a more naturalistic one, December 2, 2005 with the implication that the main reason why philosophers do not collaborate more is that they do not know how. My account of collaboration is based on my own experience, published advice by practicing scientists, and interviews with a group of highly successful scientific collaborators who are members of the Social Psychology area of the University of Waterloo Psychology Department. For the past two decades, Waterloo’s social psychology program has flourished, both in collaborative publication and in graduate training: their former Ph.D.. (shrink)

Dienes & Perner's target article contains numerous but unsystematic references to the implicit or explicit knowledge of the temporal context of a known state of affairs such as may constitute the content of a propositional attitude. In this commentary, the forms of cognition that, according to D&P, require only implicit knowledge of time are contrasted with those for which explicit temporal knowledge is needed. It is suggested that the explicit representation of time may have been (...) important in human evolution and that certain developmental disorders including autism may be (partly) caused by defective ability to represent time. (shrink)

Dienes & Perner offer us a theory of explicit and implicit knowledge that promises to systematise a large and diverse body of research in cognitive psychology. Their advertised strategy is to unpack this distinction in terms of explicit and implicit representation. But when one digs deeper one finds the “Higher-Order Thought” theory of consciousness doing much of the work. This reduces both the plausibility and usefulness of their account. We think their strategy is broadly correct, but that (...) consensus on the explicit/implicit knowledge distinction is still a fair way off. (shrink)

The Doomsday Argument says we should increase our subjective probability that Doomsday will occur once we take into account how many humans have lived before us. One objection to this conclusion is that we should accept the Self-Indication Assumption (SIA): Given the fact that you exist, you should (other things equal) favor hypotheses according to which many observers exist over hypotheses on which few observers exist. Nick Bostrom argues that we should not accept the SIA, because it can be used (...) without knowledge of birth rank. Bradley Monton tries to construct a Doomsday Argument without knowledge of birth rank. I argue that Monton fails. The argument he constructs has implicit knowledge of birth rank and it is this knowledge that does the work. Furthermore, I argue that provided we dont have certain specific information about the future, the Doomsday Argument requires knowledge of birth rank. (shrink)

Dienes & Perner's target article constitutes a significant advance in thinking about implicit knowledge. However, it largely neglects processing details and thus the time scale of mental states realizing propositional attitudes. Considering real-time processing raises questions about the possible brevity of implicit representation, the nature of processes that generate explicit knowledge, and the points of view from which knowledge may be represented. Understanding the propositional attitude analysis in terms of momentary mental states points the way (...) toward answering these questions. (shrink)

Dienes and Perner offer us a theory of explicit and implicit knowledge that promises to systematise a large and diverse body of research in cognitive psychology. Their advertised strategy is to unpack this distinction in terms of explicit and implicit representation. But when one digs deeper one finds the HOT theory of consciousness doing much of the work. This reduces both the plausibility and usefulness of their account. We think their strategy is broadly correct, but that consensus (...) on the explicit/implicit knowledge distinction is still a fair way off. (shrink)

Dienes & Perner's target article is not a satisfactory theory of implicit knowledge because in endorsing the representational theory of knowledge, the authors also inadvertently accept that only explicit knowledge can be causally efficacious, and hence that implicit knowledge is an inert category. This conflation between causal efficacy, knowledge, and explicitness is made clear through the authors' strategy, which consists of attributing any observable effect to the existence of representations that are as minimally (...) explicit as needed to account for behavior. In contrast, we believe that causally efficacious and fully implicit knowledge exists, and is best embodied in frameworks that depart radically from classical assumptions. (shrink)

This commentary focuses on how Dienes & Perner's (D&P's) claims relate to aspects of development. First, I discuss recent research that supports D&P's claim that anticipatory looking in a false belief task is guided by implicit knowledge. Second, I argue that implicit knowledge may be based on exposure to regularities in the world as D&P argue, but equally, it may sometimes be based on theories that conflict with real world regularities. Third, I discuss Munakata et al.'s (...) notion of graded representations as an alternative to the implicit-explicit distinction in explaining dissociations in infancy. (shrink)

The propositional account of explicit and implicit knowledge interprets cognitive differences between direct and indirect test performance as emerging from the elements in different hierarchical levels of the propositional representation that have been made explicit. The hierarchical nature of explicitness is challenged, however, on the basis of neuropsychological dissociations between direct and indirect tests of memory, as well as the stochastic independence that has been observed between these two types of tests. Furthermore, format specificity on indirect test of (...) memory challenges the basic notion of a propositional theory of implicit and explicit knowledge. (shrink)

Three forms of implicit knowledge are presented (functional, structural, and procedural). These forms differ in the way they are made explicit and hence in how they are represented by the individual. We suggest that the framework presented by Dienes & Perner does not account for these differences.

Knowledge-based programs (KBPs) are a powerful notion for expressing action policies in which branching conditions refer to implicit knowledge and call for a deliberation task at execution time. However, branching conditions in KBPs cannot refer to possibly erroneous beliefs or to graded belief, such as “if my belief that φ holds is high then do some action α else perform some sensing action β”.

Stanley and Williamson reject Ryle's knowing-how/knowing-that distinction charging that it obstructs our understanding of human action. Incorrectly interpreting the distinction to imply that knowledge-how is non-propositional, they object that Ryle's argument for it is unsound and linguistic theory contradicts it. I show that they (and their interlocutors) misconstrue the distinction and Ryle's argument. Consequently, their objections fail. On my reading, Ryle's distinction pertains to, not knowledge, but an explanatory gap between explicit and implicit content, and his argument (...) for it is sound. I defend the distinction's necessity in explaining human action and show that it propels a fruitful explanatory program. (shrink)

Mutual perceptual knowledge is a prevalent feature of our everyday lives, yet appears to be exceptionally difficult to characterise in an acceptable way. This paper argues for a renewed understanding of Stephen Schiffer’s iterative approach to mutual knowledge, according to which mutual knowledge requires an infinite number of overlapping, embedded mental states. It is argued that the charge of ‘psychological implausibility’ that normally accompanies discussion of this approach can be offset by identifying mutual knowledge, not with (...) the infinite iterations themselves, but with the finite base which Schiffer proves is capable of generating those iterations. An understanding of this finite base as a primitive, relational property holding between two or more people, allows us to understand the iterations as an implicit and ‘harmless’ intrapersonal feature of what is an interpersonal phenomenon. The paper concludes by relating the account to joint attention in infant interaction. (shrink)

Paul Boghossian advocates a version of the analytic theory of a priori knowledge. His defense of an "epistemic" notion of analyticity is based on an implicit definition account ofthe meaning of the logical constants. Boghossian underestimates the power of the classical Quinean criticisms, however; the challenge to substantiate the distinction between empirical and non-empirical sentences, as forcefully presented in Two Dogmas, still stands, and the regress from Truth by Convention still needs to be avoided. Here, Quine also showed (...) that there are no implicit definers for the logical constants. Moreover, even if they existed, their epistemic analyticity would, on Boghossian's own account, be doubtful. (shrink)

This paper motivates two bases for ascribing propositional semantic knowledge (or something knowledgelike): first, because it’s necessary to rationalize linguistic action; and, second, because it’s part of an empirical theory that would explain various aspects of linguistic behavior. The semantic knowledge ascribed on these two bases seems to differ in content, epistemic status, and cognitive role. This raises the question: how are they related, if at all? The bulk of the paper addresses this question. It distinguishes a variety (...) of answers and their varying philosophical and empirical commitments. (shrink)

The paper argues that the theory of Implicit Definition cannot give an account of knowledge of logical principles. According to this theory, the meanings of certain expressions are determined such that they make certain principles containing them true; this is supposed to explain our knowledge of the principles as derived from our knowledge of what the expressions mean. The paper argues that this explanation succeeds only if Implicit Definition can account for our understanding of the (...) logical constants, and that fully understanding a logical constant in turn requires the ability to apply it correctly in particular cases. It is shown, however, that Implicit Definition cannot account for this ability, even if it draws on introduction rules for the logical constants. In particular, Implicit Definition cannot account for our ability to apply negation in particular cases. Owing to constraints relating to the unique characterisation of logical constants, invoking the notion of rejection does not remedy the situation. Given its failure to explain knowledge of logic, the prospects of Implicit Definition to explain other kinds of a priori knowledge are even worse. (shrink)

Frank Jackson’s knowledge argument is a very influential piece of reasoning that seeks to show that colour experiences constitute an insoluble problem for science. This argument is based on a thought experiment concerning Mary. She is a vision scientist who has complete scientific knowledge of colours and colour vision but has never had colour experiences. According to Jackson, upon seeing coloured objects, Mary acquires new knowledge that escapes her complete scientific knowledge. He concludes that there are (...) facts concerning colour experiences that scientific knowledge can neither describe nor explain. Specifically, these facts involve the occurrence of certain non-physical properties of experiences that he calls qualia. The present research considers whether a plausible formulation of the hypothesis that science can accommodate colour experiences is threatened by a version of the knowledge argument. The specific formulation of this problem has two motivations. Firstly, before investigating whether the knowledge argument raises a problem for the claim that science can account for colour experiences, we need a plausible formulation of this claim. I argue that the idea that science can accommodate colour experiences can be formulated as the modest reductionism hypothesis. Roughly speaking, this is the hypothesis that a science that can be explanatory interfaced with current physics of ordinary matter can account for conscious experiences. Secondly, an unintelligible premise figures in Jackson’s version the knowledge argument. Namely, it is assumed that Mary possesses a complete (future or possible) scientific knowledge. Nevertheless, the type of strategy involved in Jackson’s argument can be used to target modest reductionism. By considering contemporary psychophysics and neuroscience, I characterise Mary’s scientific knowledge. First, this characterisation is intelligible. In fact, it is elaborated on the basis of descriptions and explanations of colour experiences involved in current physics and neuroscience. Second, a supporter of modest reductionism can assume that the scientific knowledge ascribed to Mary might account for colour experiences. The main conclusion of the present research is that our version of the knowledge argument fails to threaten the modest reductionism hypothesis. In fact, I endorse what can be called the “two ways of thinking” reply to the knowledge argument. According to this response, the knowledge argument shows that there are different ways of thinking about colour experiences. One way of thinking is provided by scientific knowledge. The other way of thinking is provided by our ordinary conception of colour experiences. However, the existence of these two ways of thinking does not imply the existence of facts and properties that escape scientific knowledge. It might be the case that the ordinary way of thinking about colour experience concerns facts and properties described and explained by science. The principal conclusion of the research results from two investigations. The first line of research aims to reveal and evaluate the implicit assumptions that figure in the knowledge argument. The main body of the research is dedicated to this task. The principal result of this investigation is that the knowledge argument must rely on an account of introspective knowledge of colour experiences. I argue that an inferential model of introspection provides such account. On this model, Mary’s capacity to hold beliefs about her colour experiences when she sees coloured objects requires her mastery of colour concepts. The second main investigation seeks to justify the two ways of thinking strategy. As many opponents and supporters have recently started to realise, this strategy might be charged with being ad hoc. I offer a distinctive justification of this reply to the knowledge argument. Assuming the account of introspection mentioned above, the existence of visual recognitional colour concepts might justify this strategy. A person possesses these concepts when she is able to determine the colours of objects simply by having visual experiences. (shrink)

What is the potential for improvements in the functioning of consciousness? The paper addresses this issue using global workspace theory. According to this model, the prime function of consciousness is to develop novel adaptive responses. Consciousness does this by putting together new combinations of knowledge, skills and other disparate resources that are recruited from throughout the brain. The paper's search for potential improvements in consciousness is aided by studies of a developmental transition that enhances functioning in whichever domain it (...) occurs. This transition involves a shift from the use of procedural (implicit) knowledge to declarative (explicit) knowledge. However, the potential of the transition to enhance functioning has not yet been realised to any extent in relation to consciousness itself. The paper assesses the potential for consciousness to use declarative knowledge to improve its own functioning and to thereby enhance human adaptability. A number of sources (including the practices of religious and contemplative traditions) are drawn on to investigate how this potential might be realised. (shrink)

Running head: Implicit sequence learning ABSTRACT Can we learn without awareness? Although this issue has been extensively explored through studies of implicit learning, there is currently no agreement about the extent to which knowledge can be acquired and projected onto performance in an unconscious way. The controversy, like that surrounding implicit memory, seems to be at least in part attributable to unquestioned acceptance of the unrealistic assumption that tasks are process-pure, that is, that a given task (...) exclusively involves either implicit or explicit knowledge. (shrink)

69 Thompson-Schill, S.L. _et al. _(1997) Role of left inferior prefrontal cortex 59 Buckner, R.L. _et al. _(1996) Functional anatomic studies of memory in retrieval of semantic knowledge: a re-evaluation _Proc. Natl. Acad._ retrieval for auditory words and pictures _J. Neurosci. _16, 6219–6235 _Sci. U. S. A. _94, 14792–14797 60 Buckner, R.L. _et al. _(1995) Functional anatomical studies of explicit and 70 Baddeley, A. (1992) Working memory: the interface between memory implicit memory retrieval tasks _J. Neurosci. _15, 12–29 (...) and cognition _J. Cogn. Neurosci. _4, 281–288 61 Bäckman, L. _et al. _(1997) Brain activation in young and older adults 71 Petrides, M. (1994) Frontal lobes and behavior _Curr. Opin. Neurobiol._ during implicit and explicit retrieval _J. Cogn. Neurosci. _9, 378–391. (shrink)

This paper investigates the epistemic assumptions that David Lewis makes in his account of social conventions. In particular, I focus on the assumption that the agents have common knowledge of the convention to which they are parties. While evolutionary analyses show that the common knowledge assumption is unnecessary in certain classes of games, Lewis’ original account (and, more recently, Cubitt and Sugden’s reconstruction) stresses the importance of including it in the definition of convention. I discuss arguments pro et (...) contra to argue that, although the assumption might be relevant to a descriptively adequate account of social convention, it is not required for its rational reconstruction. I then point out that Lewis’ account, properly speaking, is of common reason to believe, rather than of common knowledge, and argue that, in order to formalize aptly the distinction between reason to believe and belief, standard formal epistemic models need to be supplemented with so-called awareness structures. Finally, I stress that the notion of knowledge implicit in Lewis’ text involves interesting elements that cannot be captured in the standard propositional formalizations, but need the full expressive force of quantified epistemic logic. (shrink)

This paper provides an overview of connective knowledge. It is intended to be an introduction, expressed as non-technically as possible.

Epistemology, I will argue, is of crucial importance to the sociology of knowledge— not just by way of definition of the phenomenon under study, but also because approaches to the sociology of knowledge rely on too-often implicit epistemological stances. I will make this argument through a series of categorizations: first, I will classify the field of epistemology into its three main forms; second, I will classify the sociology of knowledge into epistemological categories; third, I will classify (...) the sociology of science into these same categories. All the while, I will be making an argument for an empirical epistemology and "agnostic" studies of knowledge. This article does not cover the field of epistemology exhaustively, but tries to offer an orderly overview of classic positions for the benefit of social scientists. (shrink)

Dienes & Perner propose a theory of implicit and explicit knowledge that is not entirely complete. It does not address many of the empirical issues, nor does it explain the difference between implicit and explicit learning. It does, however, provide a possible unified explanation, as opposed to the more binary theories like the systems and the processing theories of implicit and explicit memory. Furthermore, it is consistent with a theory in which implicit learning is viewed (...) as based on the mechanisms of the cognitive architecture, and explicit learning as strategies that exploit these mechanisms. (shrink)

Reliabilism is a theory that countenances basic knowledge, that is, knowledge from a reliable source, without requiring that the agent knows the source is reliable. Critics (especially Cohen 2002 ) have argued that such theories generate all-too-easy, intuitively implausible cases of higher-order knowledge based on inference from basic knowledge. For present purposes, the criticism might be recast as claiming that reliabilism implausibly generates cases of understanding from brute, basic knowledge. I argue that the easy (...) class='Hi'>knowledge (or easy understanding) criticism rests on an implicit mischaracterization of the notion of a reliable process. Properly understood, reliable processes do not permit the transition from basic knowledge to understanding based on inference. (shrink)

The starting point of this work is the gap between two distinct traditions in information engineering: knowledge representation and data-driven modelling. The first tradition emphasizes logic as a tool for representing beliefs held by an agent. The second tradition claims that the main source of knowledge is made of observed data, and generally does not use logic as a modelling tool. However, the emergence of fuzzy logic has blurred the boundaries between these two traditions by putting forward fuzzy (...) rules as a Janus-faced tool that may represent knowledge, as well as approximate non-linear functions representing data. This paper lays bare logical foundations of data-driven reasoning whereby a set of formulas is understood as a set of observed facts rather than a set of beliefs. Several representation frameworks are considered from this point of view: classical logic, possibility theory, belief functions, epistemic logic, fuzzy rule-based systems. Mamdani's fuzzy rules are recovered as belonging to the data-driven view. In possibility theory a third set-function, different from possibility and necessity plays a key role in the data-driven view, and corresponds to a particular modality in epistemic logic. A bi-modal logic system is presented which handles both beliefs and observations, and for which a completeness theorem is given. Lastly, our results may shed new light in deontic logic and allow for a distinction between explicit and implicit permission that standard deontic modal logics do not often emphasize. (shrink)

Implicit learning is the process through which we become sensitive to certain regularities in the environment (1) in the absence of intention to learn about those regularities (2) in the absence of awareness that one is learning, and (3) in such a way that the resulting knowledge is difficult to express.

The essay that follows considers two topics. After dealing with relevant preliminaries, it asks: (a) what differences are there in what must be done in order to tell whether there is any religious knowledge if an internalist evidentialist account of knowledge is true, from what must be done in order to tell whether there is any religious knowledge if an externalist reliabilist account of knowledge is true; and (b) does the best current externalist reliabilist account of (...) knowledge require (or perhaps already implicitly contain) an internalist evidentialist element? Put in a nutshell, then, a belief has warrant for a person S only if that belief is produced in S by cognitive faculties functioning properly (subject to no dysfunction) in a cognitive environment that is appropriate for S’s kind of cognitive faculties, according to a design plant that is successfully aimed at truth … when a belief meets these conditions and does enjoy warrant, the degree of warrant it enjoys depends on the strength of the belief, the degree of firmness with which S holds it. This is intended as an account of the central core of our concept of warrant … [Warranted Christian Belief, 156; implicit in reference to a design plan here is another feature—that the belief is subject to no undefeated defeaters; such a belief, if true, constitutes knowledge.]. (shrink)

Michael Friedman’s project both historically and systematically testifies to the importance of the relativized a priori. The importance of implicit definitions clearly emerges from Schlick’s General Theory of Knowledge . The main aim of this paper is to show the relationship between both and the relativized a priori through a detailed discussion of Friedman’s work. Succeeding with this will amount to a contribution to recent scholarship showing the importance of Hilbert for Logical Empiricism.

Implicit learning – broadly construed as learning without awareness – is a complex, multifaceted phenomenon that defies easy definition. Frensch (1998) listed as many as eleven definitions in an overview, a diversity that is undoubtedly symptomatic of the conceptual and methodological challenges that continue to pervade the field forty years after the term first appeared in the literature (Reber, 1967). According to Berry and Dienes (1993), learning is implicit when an individual acquires new information without intending to do (...) so and in such a way that the resulting knowledge is difficult to express. In this, implicit learning thus contrasts strongly with explicit learning (e.g., as when learning how to solve a problem or learning a concept), which is typically hypothesisdriven and fully conscious. Implicit learning is the process through which one becomes sensitive to certain regularities in the environment: (1) without trying to learn regularities, (2) without knowing that one is learning regularities, and (3) in such a way that the resulting knowledge is unconscious. (shrink)

In this paper non-normal worlds semantics is presented as a basic, general, and unifying approach to epistemic logic. The semantical framework of non-normal worlds is compared to the model theories of several logics for knowledge and belief that were recently developed in Artificial Intelligence (AI). It is shown that every model for implicit and explicit belief (Levesque), for awareness, general awareness, and local reasoning (Fagin and Halpern), and for awareness and principles (van der Hoek and Meyer) induces a (...) non-normal worlds model validating precisely the same formulas (of the language in question). (shrink)

We present a theoretical account of implicit and explicit learning in terms of ACT-R, an integrated architecture of human cognition as a computational supplement to Dienes & Perner's conceptual analysis of knowledge. Explicit learning is explained in ACT-R by the acquisition of new symbolic knowledge, whereas implicit learning amounts to statistically adjusting subsymbolic quantities associated with that knowledge. We discuss the common foundation of a set of models that are able to explain data gathered in (...) several signature paradigms of implicit learning. (shrink)

This paper considers different subjective measures of conscious and unconscious knowledge in a concept formation paradigm. In particular, free verbal reports are compared with two subjective measures, the zero-correlation and the guessing criteria, based on trial-by-trial confidence ratings (a type of on-line verbal report). Despite the fact that free verbal reports are frequently dismissed as being insensitive measures of conscious knowledge, a considerable bulk of research on implicit learning has traditionally relied on this measure of consciousness, because (...) it is widely regarded as almost self-evident that the content of any conscious state that is intentional and conceptual can be expressed verbally. However, we found that the most recently developed subjective measures based on trial-by-trial confidence ratings provided a more sensitive measure of conscious and unconscious knowledge than free verbal reports. In a complementary way, the qualitative pattern of the free report and the confidence measures were similar, providing further evidence for the validity of the latter. (shrink)

Scientific discourse leaves implicit a vast amount of knowledge, assumes that this background knowledge is taken into account – even taken for granted – and treated as undisputed. In particular, the terminology in the empirical sciences is treated as antecedently understood. The background knowledge surrounding a theory is usually assumed to be true or approximately true. This is in sharp contrast with logic, which explicitly ignores underlying presuppositions and assumes uninterpreted languages. We discuss the problems that (...) background knowledge may cause for the formalization of scientific theories. In particular, we will show how some of these problems can be addressed in the context of the computational representation of scientific theories. (shrink)

Dienes & Perner present a very interesting analysis of two types of knowledge. It is not clear, however, that the words “implicit” and “explicit” are the best basis on which to build a theory of the two types of knowledge. One is also left uncertain as to whether this theory is the best way of ordering the greatest possible amount of relevant data in a way that yields the simplest account possible.

According to the ?story model? a juror constructs an implicit mental model of a story telling what happened as the basis for the verdict choice. But the explicit justification of a verdict choice could take the form of a story (knowledge telling) or the form of a relational (knowledge-transforming) argument structure that brings together diverse, non-chronologically related pieces of evidence. The study investigates whether people tend towards knowledge telling or knowledge transforming, and whether use of (...) these argument structure types are related to skilled argument and epistemic understanding. A sample of people on jury duty chose and justified verdicts in two abridged cases. Participants tended to display the same argument structure and argument skill across cases. Those using knowledge-transforming structures were more successful at the juror argument skills task and had a higher level of epistemic understanding. The discussion suggests that jurors approach their task with an epistemic orientation towards knowledge telling or knowledge transforming. (shrink)